1. Field of the Invention
This invention relates to a vibratory conveyor having a linear drive unit that includes a base and a trough support interconnected by a plurality of leaf springs.
2. Description of the Prior Art
Vibratory conveyors have base and trough assemblies that are interconnected by leaf springs to provide for vibratory movement. Both assemblies have masses that, upon vibratory movement, create inertia forces acting at the centers of mass of each assembly. These inertia forces form a force couple that tends to rotate or rock the whole conveyor longitudinally on its mounting. To compensate for such rotational motion, leaf springs have been arranged in non-parallel relationship within the vertical planes of their vibration paths. Such leaf spring arrangements are disclosed by U.S. Pat. No. 3,216,556 that issued Nov. 9, 1965, to W. C. Burgess, Jr. and by my co-pending U.S. application, Ser. No. 912,806, that was filed June 5, 1978 now issued as U.S. Pat. No. 4,260,052.
These leaf spring angles of inclination have also been adjusted to provide desired vibration angles for the trough assembly. Maximum feed rates can be achieved for various granular materials by making such adjustments. A driver for generating vibrational forces should be mounted perpendicular to the leaf springs, or tangential to their arcuate paths of vibrational travel, for efficient utilization of the vibratory forces developed. Otherwise, the leaf springs do not bend readily, and such springs transfer axial forces that are resistive to desired movement between the base and trough assemblies.